Glossary

Affective empathy is the capacity to share, resonate with, or be emotionally affected by another person's emotional state. It is conceptually and empirically distinct from cognitive empathy, which is the capacity to identify and accurately model another person's mental state without necessarily sharing it.

The Big Five personality model (also called OCEAN or Five-Factor Model) is the most empirically validated framework for measuring personality, comprising five broad trait dimensions.

Cache warming is the practice of pre-populating a cache with data before live traffic arrives, so the first request after a cache flush hits a warm cache rather than triggering an expensive cold rebuild.

A ceiling effect is a measurement problem where a substantial proportion of respondents score at or near the maximum possible value on a scale, reducing the variance available to distinguish between high scorers.

Classical Test Theory (CTT) is a psychometric framework that models an observed test score as the sum of a person's true score and random measurement error.

Cluster analysis is a family of unsupervised multivariate methods that partition cases into groups (clusters) such that cases within a group are more similar to each other than to cases in other groups. The technique discovers structure in data without requiring a pre-specified outcome variable.

Cognitive empathy is the ability to identify, understand, and accurately model another person's thoughts, beliefs, perspectives, and emotional states. It is conceptually and empirically distinct from affective empathy, which concerns the capacity to share or resonate with another person's emotions.

Confirmatory Factor Analysis (CFA) is a statistical technique that tests whether observed variables (e.g., questionnaire items) conform to a hypothesized underlying factor structure.

A construct definition is a precise specification of the theoretical concept a test or assessment is designed to measure, including its boundaries, dimensionality, and the behaviors or attitudes it should and should not encompass.

Construct validity is the degree to which a test or assessment accurately measures the theoretical construct (such as intelligence, personality, or motivation) it purports to measure.

A content model is a formal definition of the content types, their fields, relationships, and constraints within a content management system or website.

A context window is the maximum number of tokens (words and word fragments) that a large language model can process in a single conversation, encompassing both input and output.

Convergent validity is the degree to which a test correlates with other measures of the same or theoretically related constructs, providing evidence that the test is in fact measuring the construct it claims to measure.

Criterion validity is the degree to which scores on a test correlate with an external criterion the test is supposed to predict or explain, evaluated either concurrently (criterion measured at the same time as the test) or predictively (criterion measured later).

Cron is the time-based job scheduler built into Unix-like operating systems, used to run scripts or commands on a recurring schedule defined in a crontab file.

Cronbach's alpha is a coefficient of internal-consistency reliability that estimates how well a set of test items measures a single underlying construct, based on the average inter-item correlation.

Discriminant validity is the degree to which a test correlates less strongly with measures of theoretically distinct constructs than with measures of the same construct, providing evidence that the test is not redundant with neighboring measures.

Distractor analysis is the examination of how frequently each wrong-answer option on a multiple-choice test item is selected, used to identify non-functional ('dead') distractors and improve item quality.

E-E-A-T (Experience, Expertise, Authoritativeness, Trustworthiness) is a framework from Google's Search Quality Rater Guidelines used to evaluate the quality and credibility of web content.

Face validity is the degree to which a test, in the judgment of the people taking it or evaluating it, appears on its surface to measure the construct it claims to measure. It is the most superficial form of validity evidence and not a substitute for empirical validation, but it carries social and operational weight that other validity types do not.

Fail2ban is an intrusion prevention tool that monitors system log files for patterns of malicious activity and automatically bans offending IP addresses using firewall rules.

FastCGI cache is an Nginx feature that stores the complete HTML output of PHP requests as static files, serving subsequent requests directly from cache without invoking PHP.

A forced-choice assessment is a measurement format in which respondents must select between two or more items rather than rate each item independently, eliminating uniform endorsement and reducing socially desirable response bias.

The Gallup Q12 is a 12-item employee engagement survey developed by Gallup in the 1990s, used to measure conditions and outcomes associated with engaged work behavior across organizations and industries.

IndexNow is an open protocol that allows websites to notify participating search engines (Bing, Yandex, others) immediately when content is created, updated, or deleted.

Internal consistency is the degree to which the items composing a scale agree with each other, providing evidence that the items are measuring the same underlying construct. The most common estimators are Cronbach's alpha and McDonald's omega, both of which use inter-item covariance to summarize agreement.

Internal linking is the practice of connecting pages within the same website through hyperlinks, distributing page authority and establishing topical relationships for search engines.

Ipsative measurement is a scoring approach in which an individual's scores on a set of traits sum to a constant, producing scores that describe within-person trait priorities rather than between-person trait levels.

Item discrimination is a psychometric statistic describing how well a single test item separates examinees who score high on the overall test from those who score low, typically expressed as a point-biserial correlation between item response and total score.

Item Response Theory (IRT) is a family of statistical models that describe the relationship between a person's latent trait level and their probability of responding correctly to a test item.

An AI knowledge base is a structured repository of project context, decisions, conventions, and domain knowledge that persists across LLM conversations, enabling continuity and informed assistance.

A LEMP stack is a software bundle of Linux, Nginx (Engine-X), MariaDB (or MySQL), and PHP used to serve dynamic web applications.

A Likert scale is a psychometric response format where respondents rate their agreement with a series of statements on an ordered set of categories — most commonly 5 or 7 points from strongly disagree to strongly agree.

O*NET (Occupational Information Network) is a comprehensive database maintained by the US Department of Labor that describes occupations in terms of skills, abilities, knowledge, work activities, and interests.

OPcache is PHP's built-in opcode cache that stores pre-compiled script bytecode in shared memory, eliminating the need to parse and compile PHP files on every request.

Ordinal data is data measured at a level where categories have a meaningful order (1 is less than 2 is less than 3) but the spacing between adjacent categories is not guaranteed to be equal. Most rating-scale data in survey research, including Likert items and NPS responses, is ordinal.

Outcome-based pricing is a SaaS pricing model in which customers pay based on measurable business results delivered by the product, such as transactions completed or time saved, rather than on headcount, usage volume, or feature tier.

PHP-FPM (FastCGI Process Manager) is a PHP implementation that manages a pool of worker processes to handle PHP requests from a web server like Nginx.

A psychometric assessment is a standardized measurement instrument designed to quantify psychological attributes such as personality traits, cognitive abilities, interests, or values.

Redis object cache is an in-memory data store used by WordPress to cache database query results, reducing the number of MySQL queries needed to generate each page.

Response bias is any systematic tendency for respondents to answer items in ways that reflect something other than their true position on the construct being measured. The most common forms are social desirability, acquiescence, central tendency, extreme responding, and impression management.

Restic is an open-source backup tool that creates encrypted, deduplicated, incremental backups using a content-addressed snapshot model, with support for local storage, S3-compatible object storage, and most major cloud providers.

A situational judgment test is an assessment format that presents respondents with workplace scenarios and asks them to evaluate or select among possible behavioral responses, providing a measure of practical judgment, role-relevant competence, or values alignment.

Social desirability bias is the systematic tendency for respondents to answer items in ways that present themselves in a socially favorable light, either by overreporting desirable behaviors and attitudes or by underreporting undesirable ones. It is the most studied and most consequential form of response bias in self-report assessment.

Specification-driven development is an approach where detailed written specifications guide implementation, particularly effective when using AI coding assistants that perform better with explicit requirements than vague instructions.

An SSL/TLS certificate is a digital credential that enables encrypted HTTPS connections between a web browser and server, verifying the server's identity and protecting data in transit.

A static site generator (SSG) is a tool that builds a complete website as pre-rendered HTML files at compile time, rather than generating pages dynamically on each server request.

Structural Equation Modeling (SEM) is a multivariate statistical framework that tests hypothesized relationships among observed and latent variables simultaneously, combining factor analysis with path analysis.

Structured data is machine-readable code (typically JSON-LD format) embedded in web pages that describes content to search engines using the Schema.org vocabulary.

Switching cost is the total economic, operational, and cognitive effort required for a customer to replace one product or service with another, including data migration, retraining, integration rework, and risk of disruption.

Transient cleanup is the periodic removal of expired and orphaned WordPress transients — short-lived cached values stored in the wp_options table that persist past their expiry and bloat the database.

UFW (Uncomplicated Firewall) is a user-friendly command-line front-end to Linux's iptables or nftables firewall, designed to make common firewall tasks simple without hiding the underlying ruleset.

A Virtual Private Server (VPS) is a virtualized server environment that provides dedicated CPU, RAM, and storage resources within a shared physical machine.

Watchdog monitoring is the practice of running health checks from an external machine, independent of the server being monitored, so total outages are detected even when the primary host cannot report its own state.

A Wright map is a two-panel visualization from Item Response Theory that plots examinee ability and item difficulty on a shared logit scale, revealing whether a test's difficulty distribution matches the population it measures.